First of all, I am making no comparison to Terraria, as after playing both for hours, they are completely different once you look past the "2D Minecraft Shell." In saying that, Terraria does one thing I do like. I'm the kind of person who enjoys "alts," whether it is to try all classes or races in a game. What I would love to see is the option, and purely an option, that if I make a new character, he or she could share a universe with my other characters. In this, I could build a town, and see it (provided I fly there with my other characters) on my multiple characters. This could be fun for some people, and if others don't like it, keep an option to generate a new universe per character.
I kinda like this idea. But i think it's already easily achieved by "making a server" just for you and playing only in multiplayer. I'm not sure how heavy it is for the computer to handle it, i never messed with servers
Did not know that, thanks I found a planet I was working on with an alt, and nothing was there, so maybe it was a bug then or something. But good to know.